Switch



2 Sheets-Sheet v b M a M w w... W m m m 2 W MMM Y W M Nov. 13, 1934. c.J. WERNER SWITCH led Oct. 27. 1932' Nov. 13, 1934. WERNER 51,930,457

SWITCH Filed Oct. 27. 1952" 2 Sheets-Sheet 2 CAL m J WEE NEE? PatentedNov. 13, 1934 SWITCH Calvin J. Werner, Dayton, Ohio, assignor, by

mesne assignments, to General Motors Corporation, Detroit, Mich., acorporation of Delaware Application October 27,

14 Claims.

' This invention relates to a switch and more particularly to a switchfor controlling an electrical circuit.

It is an object of this invention to provide a switch adapted for manualcontrol and having means for automatically interrupting a circuit inresponse to abnormal current flow thru said circuit.

Another object of this invention is to provide a switch capable ofmanual operation that breaks the circuit with a snap action regardlessof the speed of manual operation.

Another object of this invention is to provide a switch that may bemanually operated and that may be automatically opened, and that whetherautomatically or manually opened, opens with a snap action.

Another object of this invention is to provide a switch embodying athermostatic control assembly that is separable therefrom as a unit andchangeable without altering the remainder of said switch.

Another object of this invention is to provide a switch having anadjustment for controlling the fiexure of the thermostatic member thatis necessary to permit the automatic operation of the switch.

Still another object of this invention is to provide a switch that isadaptable to a variety of uses, and which while having adjustments andchangeable elements to fit such uses, still lends itself to convenienceand ease of manufacture as well as low cost and ruggedness.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings wherein a preferred embodiment of one form of the presentinvention is clearly shown.

In the drawings:

Fig. 1 is a perspective view of a switch embodying the presentinvention, and shows the contacts in the open or disengaged position.

Fig. 2 is also a perspective view of the switch, and shows the contactsin the closed or engaged position.

Fig. 3 is an elevation of the switch showing some of the details ofconstruction.

Fig. 4 is also an elevation of the switch taken substantially asindicated by the arrows 44 in Fig. 3.

Fig. 5 is a sectional view of the switch taken substantially on the linein the direction of arrows 5-5 of Fig. 4.

Fig. 6 is a partially fragmentary sectional view 1932, Serial No.639,750-

ing a modification in some of the pivotally mountd parts of the switch.

Fig. 8 is an elevation showing the modification indicated in Fig. 7.

With particular reference to the drawings,

brackets 10 and 12 are secured to amounting 14 that is preferably madeof insulating material. Angle members 13 and 15 are secured to themounting 14 by rivets 17 and 19 respectively, or other suitable meansand are for use in mounting the switch. The bracket 10 has a portion 16that forms a support for a portion of the switch structure. Asubassembly comprising a cam member 18, preferably made of insulatingmaterial, a'lever arm 20 having angularly disposer' extensions 22 and24, and a link 26 is pivfially mounted to the portion 16 of bracket 10on a pin or shaft 28. A sleeve 30 surrounds the midportion of the pin orshaft 28, and extends from the extension 24 through the extension 22 andthe portion 16 of the bracket 10 to a pivotally mounted member 32 towhich the pin or shaft 28 was secured. The sleeve 30 thus acts as aspacer and insures free rotary motion of the subassembly. The member 32is pivotally mounted to the portion 16 of the bracket 10 by a rivet 34or any suitable means. A screw 36 projects through an elongated aperture38 in the pivotally mounted member 32 and is threaded into the portion16 of the bracket 10 so that the member 32 may be pivotally moved aboutthe rivet 34 when the screw 36 is loosened, and will be clamped or heldin position when the screw 36 is tightened.

The member 40 having an angular extension 42 is slidably mounted on thelever arm 20 by means of rivets 44 and 46 having shoulder portions 52and 54 respectively that are slidable in elongated apertures 48 and 50in the member 40. The rivet 46 has an extension 56 to which springs orresilient members 58 and 60 are connected.

The spring 58 is also connected to the bracket 10 through 2. lug 62 thatis struck from the bracket. An operating lever 64 projects through anaperture 66 in the mounting l4 and through an aperture 68 in the angularextension 42 of the slidably mounted member 40. The end of the operatinglever 64 that projects through the aperture 68 is connected to thespring 60, and the operating lever is provided with a shoulder '70 thatis urged against the angular extension 42 by the spring 60. The pressureof the shoulder 70 against the extension 42 tends to slide the slidablymounted member 40 so that the shoulders 52*and 54 of the rivets 44 and46 rest at the ends of the apertures48 and 50,. and an end 72 of theslidably mounted member 40 projects beyond the end of the lever arm 20.The

' spring 58 urges or biases the subassembly formed by the cam member 18,the lever arm 20 and the slidably mounted member 40 to rotate in onedirection about their pivotal mounting formed by the pin or shaft 28.

The brackets 10 and 12 are preferably secured to the mounting 14 byscrews 73 and 74 respectively'threaded into angularly disposed portionsof the brackets. The stationary contact carrying member 76 has a portionlocated intermediate the bracket 10 and mounting 14 so that it is heldin place by the screw 73. A resilient contact carrying member'78 issecured'to the mounting 14 preferably by means of a screw 80 and acooperating nut 82. The contact carrying member 78 has a lug 84 formedon one end and projecting into an aperture 86 in the mounting 14 toprevent the member from turning. The contact carryingmember 76v and theresilient contact carrying member 78. have cooperating contacts 88 and90 respectively secured thereto. The resilient contact carrying member78 is normally biased so as to urge the contacts 88 and 90 intoengagement. 'Then, the resilient contact carrying member '78 extends toa position in cooperative relation with the cam member 18 so.

that movement of the cam in one direction causes it to engage theresilient contact carrying memto hold the bolt in position when the.latch assembly is removed. A stop member 116 is secured to the bracket10 by the bolt 100, and washers 118 and 120 and a nut 122 on the bolt100 serve as spacers and hold that bolt and the stop member 116 in.position when the latch assembly is removed.

The thermostatic latch assembly includes a strip or block 124 ofinsulating and heat resisting material having an elongated opening 126therein and apertures 128 and 130 therethrough for the accommodation ofthe bolts 100 and 102 respectively. The apertures 128 and 130 havesleeves 132 and 134 respectively therein which sleeves have rolled orriveted end portions to secure them in position. The opening 126 has ashoulder portion 136 formed therein at one end thereof to which athermostatic member or bimetallic strip 138 is secured by a rivet 140 orother suitable means. An end portion 142 of the rivet 140 is set into arecess 144 in the block or strip 124 so that the rivet is totally withinthe confines of the block or strip 124. A coil of resistance wire orheating element 146 is space-wound on the block or strip 124 so that rit is exposed to more than one side of-the thermostatic member. 138 andsurrounds a portion of that member, and is spaced therefrom so as -notto impede or restrain the flexure of, the

thermostatic member caused by heat. The ends 1 of the coil 146 areelectrically connected to the 178 within the apertures.

bolts 100 and 102, and washers 148 and 150 are placed intermediate thenuts 104 and 106 respectively and the block or strip 124. Thethermostatic member 138 has an angularly extending portion 152 thatprojects from the opening 126 to engage the extending portion 72 of theslidably mounted member 40 to latch or hold the pivotally mountedsubassembly against the urging force of the resilient member 58 topermit the contacts to remain in the closed or engaged position whilethe subassembly is thus held.

A lug 154 located intermediate the head of the screw 80 and the mounting14, and preferably having a screw 156 threaded therein forms oneterminal for the switch and is connected to the contact 90through thescrew 80 and the contact carrying member 78. The contact carrying member76 is electrically connected to the bracket 10 by-virtue of its beingheld in positionintermediate the bracket 10 and the mounting 14 by thescrew 73. The bracket 10 is electrically connected to one end of theresistance coil or heating element 146 thru the bolt 100, and the otherend of the coil 146 is connected to the bracket 12 through the bolt 102which bolt .is insulated from the bracket 10. A lug 158 locatedintermediate the head of the screw 74 and the mounting 14 and preferablyhaving the screw 160 threaded therein forms the other terminal of theswitch. Lock washers 162 and 164 are provided for the screws 80 and 74respectively to prevent them from loosening. It may thus be seen thatthe brackets 10 and 12 form a part of the switch circuit, and that theresistance coil or heatingelement 146 is connected in series with thecontacts so that the heat applied to the thermostatic member 152 isproportional to the current through the switch circuit.

With particular reference to Figs. 7 and 8, the parts bearing referencenumerals .to those previously used are similar and perform similarfunctions. However, in this modification apertures and 172 are providedin the lever arm 20 and slidably mounted member 40 respectively. A lug174 is formed at one end in the aperture 170, and 2. lug 176 is formedat one end of the aperture 172 so that the said lugs are oppositelydisposed and adapted to hold a spring or resilient member The spring orresilient member 178 then urges the slidaby mounted member 40 in onedirection so that the shoulder portions 52 and54 of the rivets 44 and 46respectively are disposed at the ends of their respective elongatedapertures 52 and 54 respectively,

and so that the end portion 72 of the slidably,

mounted member 40 projects beyond the end of the lever arm 20.

In the operation of the switch, assuming it in the off of contactdisengaging. position as shown in Fig. 1, it may be manually operated toengage the contacts by substantially linear movement of the operatingmember 64 so that the shoulder 70 is forced against the portion 42 ofthe slidably mounted member 40. The force thus applied larly extendingportion 152 of the thermostatic member 138 and causes it to flex untilthe end portion 72 passes the end of the thermostatic member 138sufticiently to permit a latching engagement. The switch then assumes aposition substantially as shown in Fig. 2.

Then, to open or disengage the contacts manually the operating member 64is moved substantially linearly in a direction opposite to that forcausing engagement of the contacts. When the operating member 64-hasbeen sufficiently moved, the end portion of the spring or resilientmember engages the angular extension 42 of the slidably mounted member40 and causes that member to slide relative to the lever arm 20 untilthe end portion 72 of the member becomes disengaged from the end of thethermostatic member 138. When disengagement is thus accomplished, thepivotally mounted subassembly is rotated by virtue of the urging forceof the spring or resilient member 58 to a position such that the endportion '72 of the slidably mounted member 40 rests against the stopmember 116. When the operating member 64 is then released, the urgingforce of the spring or resilient member 60 urges by the switch is causedto flow through the resistance coil or heating element 146, the heatproduced in that coil or element is proportional to the current fiowthrough the switch. Hence, in the event of an abnormal condition such asan excessive current flow through the switch, the thermostatic-member138 is caused to flex and to automatically be disengaged from theportion '72 of the slidably mounted member 40 to permit rotation of thepivotally mounted subassembly and disengagement of the contacts in amanner similar to that previously described.

An adjustment has been provided to permit regulation or adjustment ofthe fiexure of the thermostatic member 138 necessary to eifect releaseor disengagement of that member from the portion 72 of the slidablymounted member 40. An adjustment is also desirable to compensate forslight variations in the size of parts in manufacture. This adjustment.is accomplished in the present switch through the mounting of thepivotally mounted subassembly on the adjustable pivotally mounted member32. Movement or adjustment of the member 32 shifts the position of thepin or shaft 28 and hence the position of the pivotally mountedsubassemby relative to the end of the thermostatic member 138 so thatthe portion 72 of the slidably mounted member 40 may be caused to engagethe end of the thermostatic member to a greater or lesser degree. Thethermostatic latch assembly comprises a unit that may be removed orreplaced without disturbance to the rest of the switch structure. Sincethe thermostatic member 138 is exposed on more than one side to theresistance coil or heaing element 146, and since the intervening heattransferring medium is air and a good conveyor of heat, the heattransfer emciency of the assembly is high. That efiiciency is alsoimproved by virtue of the thermostatic member 138 being disposed withinthe confines of the opening 126. The fiexure of the thermostatic member138 is substantially unrestrained because of the spacing of the otherparts in the assembly therefrom. Although one form of the thermostaticlatch assembly is disclosed it is to be undersLood that other formsmight be used with this switch structure without departing from thespirit of the invention.

In the modification shown in Figs. 7 and 8 a compression spring is shownthat performs substantially the same function as the spring or resilientmember 60 previously described.

While the form of embodiment of the present invention as hereindisclosed, constitutes a preferred form, it is to be understood thatother forms might be adopted, all coming within the scope of the claimswhich follow.

What is claimed is as follows:

1. A switch, comprising in combination, an insulating mounting having anaperture therein, brackets secured to said mounting, a contact carryingmember secured to said mounting, a resilient contact carrying memberalso secured to said mounting, said contact carrying members havingcontacts mounted thereon and in cooperative relation, said resilientcontact carrying member being normally biased so as to cause saidcontacts to-engage, a cam rotatably mounted on one of said brackets andlocated in position to engage said resilient contact carrying member, alever armsecured to said cam and rotatably mounted therewith, a memberslidably mounted on said lever arm and having an angularly projectingextension at one end, a resilient member urging said cam against saidresilient contact carrying member and overcoming the said normal biasingforce to separate said contacts, a thermostatic latch positioned toengage the slidably mounted member and hold said cam away from saidresilient contact carrying member against the urging of said resilientmember, a heating element associated with said thermostatic latch andelectrically connected to one of said contacts which element ifsufiiciently heated causes said latch toflex and disengage said slidablymounted member to permit said resilient member to separate saidcontacts, and a manual operating member extending through the aperturein said mounting and engaging said angularly projecting extension formanually causing said slidably mounted member to engage said latch andfor sliding said slidably mounted member to cause it to be disengagedfrom' said latch.

2. A switch, comprising in combination, a mounting, brackets secured tosaid mounting, cooperating contacts, one of said contacts being fixedlymounted, means providing a resilient mounting for another of saidcontacts and normally biasing said contacts into engagement, cam meansrotatably supported by one of said brackets, said cam being located inposition to engage said resilient mounting means to disengage saidcontacts when said cam is rotated, a lever arm secured to said cam androtatably mounted therewith, a member slidably mounted on said lever armand having an angular extension at one end and normally projectingbeyond said lever arm at its other end, a first resilient member tendingto rotate said cam and lever arm about their pivotal mounting to forcesaid contacts apart, a second resilient member urging said slidablymounted member to project beyond the end of said lever arm, athermostatic latch for engaging the pro= the end of said slidablymounted member, and an operating member engaging the angular extensionof said slidably mounted member, said operating member providing meansfor manually engaging and disengaging the projecting end of saidslidably mounted member and said thermostatic latch to open and closesaid contacts.

3. A switch, comprising in combination, a mounting, brackets secured tosaid mounting, cooperating contacts, one of said contacts being fixedlymounted, means providing a resilient mounting for another of saidcontacts and normally biasing said contacts into engagement, cam meansrotatably supported by one of said brackets, said cam being located inposition to engage said resilient mounting means to disengage saidcontacts when said cam is rotated, a lever arm secured to said cam androtatably mounted therewith, a

member slidably mounted on said lever arm and having an angularextension at one end and normally projecting beyond said lever arm atits other end, a first resilient member tending to rotatesaid cam andlever arm about their pivotal mounting to force said contacts apart, asecond resilient member urging said slidably mounted member to projectbeyond the end of said lever arm, a latch for engaging the projectingend of said slidably mounted member to hold said cam in a position topermit said contacts to engage, and an operating member engaging-theangular exten-' sion of said slidably mounted member, said operatingmember providing means for engaging and disengaging the projecting endof said slidably mounted member and said latch to open and close saidcontacts. 1

4. A switch, comprising in combination, a mounting, a bracket secured tosaid mounting, cooperating contacts normally biased into engagement, cammeans rotatably supported by said bracket, said cam providing means fordisengaging said contacts, a thermostatic latch member,

said thermostatic latch .member being adapted to flex in response totemperature change, spring urged extensible means rotatably supportedwith and secured to said cam for engagement with said latch, resilientmeans for rotating said cam when said latch and extensible means becomedisengaged, and a linearly movable operating lever attached to saidextensible means for eifecting,

manually the engagementand disengagement of said extensible means andthermostatic latch to cause engagement and disengagement of saidcontacts.

5. A switch, comprising in combination, a mounting, a bracket secured tosaid mounting, cooperating contacts normally biased into engagement, cammeans rotatably supported by said bracket, said cam providing means fordisengaging said contacts, a latch member, spring urged extensible meansrotatably supported with and securedv to said cam for engagement withsaid latch, resilient means for rotating said cam when said latchandextensible means become disengaged, and a linearly movable operatinglever attached to said extensible means for efiecting manually theengagement and disengagement of said extensible means and said latch tocause engagement and disengagement of said contacts.

contacts into engagement, a pivotally mounted cam means for efiectingengagement and disengagement of said contacts, a latch for engaging saidcam means, a pivotally movable member supporting said pivotally mountedcam means for changing the position of the pivotal mounting of thepivotally mounted cam means and regulating the engagement of said cammeans with said latch, and means for holding said pivotally movablemember in a predetermined position.

7. In a switch for controlling an electrical ciredit, the combinationcomprising, cooperating contacts, means for efiecting engagement anddisengagement of said contacts, said means being normally biased todisengage said contacts, a thermostatic latch adapted to flex inresponse to heat produced by current flow in said circuit, saidthermostatic latch engaging said means when said contacts are engaged,means for adjusting the distance of fiexure necessary to permit therelease of said means, and manually operable means for actuating themeans for effecting engagement and disengagement of the contacts.

8. In a switch, the combination comprising, cooperating contacts havingan engaged and a disengaged position, means for efiecting movement ofsaid contacts to said positions, said means being normally biased to oneof said positions,

a thermostatic latch adapted to flex in response'totemperature change,said thermostatic latch engaging said means to permit said contacts toremain in one of said positions against the normal biasing, and meansfor adjusting the distance of flexure necessary to permit the release ofsaid means from said latch.

9. In a switch, the combination comprising, cooperating contacts havingan engaged and a disengaged position, means for effecting movement ofsaid contacts to said positions, said means being normally biased to oneof said positions, a thermostatic latch adapted to flex in response totemperature change, said thermostatic latch engaging said means topermit said contacts to remain in one of said positions against thenormal biasing, means for adjusting the distance of flexure necessary topermit the release of said 1 means from said latch, and manuallyoperable means for actuating. the means for efiecting movement of saidcontacts.

10. In a switch for controlling an electrical circuit, the combinationcomprising, cooperating contacts having an engaged and a disengagedposition, means for effecting movement of said contacts to saidpositions, said means being normally biased to'one of said -positions,-a thermostatic latching means for engaging said means in one of saidpositions and disengaging said means in response to temperature changeand including, a thermostatic member that flexes due to temperaturechange, a block form having an opening therein for the accommodation ofsaid thermostatic member, said member being secured at one end in saidopening and having another end projecting therefrom, and a heatingelement in heat transferring relation with more than one side of saidthermostatic latch and spaced therefrom and connected in series withsaid contacts in said circuit.

11. In a switch for controlling an electrical circuit, the combinationcomprising, cooperating contacts having an engaged and a disengagedposition, means for efiecting movement of said contacts to saidpositions, said means being normal 1y biased toone of said positions, athermostatic latching means for engaging said means in one of saidpositions and disengaging said'means in response to temperature changeand including, a thermostatic member that flexes due to temperaturechange, a block form having an opening therein for the accommodation ofsaid thermostatic member, said member being secured at one end in saidopening and having another end projecting therefrom, and a heatingelement in heat transferring relation with more than one side of saidthermostatic latch and spaced therefrom and connected in series withsaid contacts in said circuit, said heating element offeringsubstantially no restraint to the fiexure of said thermostatic member.

12. In a switch, a thermostatic latch assembly, comprising incombination, a strip of insulating material having an openingtherethrough, a heater coil wound on said strip so that the turnsthereof cross said opening, a thermostatic latch member secured at oneend to said strip and having a portion thereof surrounded by the turnsof said coil, means for making connections to said coil, and means formounting said strip on the switch.

13. In a switch, a thermostatic latch assembly, comprising incombination a thermostatic memher, a block of insulating material havingmeans for the accommodation of the major portions of said thermostaticmember within the confines of the planes defined by the outer surfacesof said block, said thermostatic member having one end secured to'saidblock and the other end free to move in response to the flexing of saidmember, a heater coil wound on said block so as to surround a portion ofsaid thermostatic member and so as to be spaced therefrom, means formaking connections to said heater coil, and means for mounting saidblock.

14. In a heat responsive control assembly for a. switch, the combinationcomprising, a thermostatic member, heat confining walls on morethan oneside of said thermostatic member, said walls being spaced from saidthermostatic member, a heater element in heat transferring relation withmore than one side of said thermostatic member only a single heattransferring medium intermediate said heater element and two sides ofsaid thermostatic member to provide said heat transferring relation, andsaid medium ofiering substantially no impedance to the flexureof thethermostatic member, means for supporting said walls, and means formaking electrical connection to said heater element.

CALVIN J. WERNER.

